Process for reduction of ores.



'GQP. RBNDALL. PROCESS FOR REDUCTION OF ORES. APPLICATION FILED JUNE 23, 1908 RENEWED JULY}, 1912.

1,053,436, Patented Feb. 18, 1913. v v I 2 SHEETS-SHEET 1.

Fl G. 1.

a. FJRENDALL.

PROCESS FOR REDUCTION OF ORE-S.

Arrmoxnon'rnnn wu 23, 1908 RENEWED JULY 2, 1912.

WITNESSES "NM 08 gay 4/, g f ff Patented Feb/18, 1913.

I UNITED sTA Es PATENT OFFICE.

- GEORGE FREDERICK RENDALL, or NEW YORK, N. Y., ASSIGNOR To R. w. PRIEST,

. TRUSTEE, on NEW YORK, N. Y.,

PROCESS FOR REDUCTION OF ORES.

Specification of Letters Patent.

Patented Feb. 18, 1913.

Application filed June 23, 1908, Serial No. 440,047. Renewed July 2; 1912. Serial No. 707,350.

To all whom, it may concern Be it known that I, GEORGE FREDERICK KENDALL, a citizen of the United States, residing in the city of New York, county of- New York, and State of New York, have invented a new and useful Process for Reduction of Ores, of which the following is a specification. Y

My invention relates to the method of treating metal ores and is particularly well adapted, to remove all the impurities from metals before reducingthem to a molten condition so that the silica and associated material are separated without the utiliza tion of fluxes whereby great economy is effected.

It consists of subjecting the ore, which has previously been heated, to-the action of hydro-carbon gases and. varying thesegases tomeet the different conditions existing 1n the ore and then discharging the reduced ore into a cooling chamber, wherebyreoxidation is prevented.

It further consists of combining the metallic oxids, which are separated from the ore, with a suitable binding material to form briquets, which latter may then be readily melted in a cupfola furnace,

It further consists of other novel features of construction, all as will be hereinafter fully set forth: v j

- Flgure 1 represents a plant wherein the process embodying my invention is carried out. Fig. 2 represents a modification of the plant disclosed in Fig. 1 wherein my process is carried out' on a different gradeof ore.

Fig. 3 represents a section through the cooling cylinder.

'Similar' numerals of' reference. indicate corresponding parts in the figures.

Referring to' the drawings .:-'-1 designates a hopper adapted to receive ore which has been crushed to asuitable size after it is received directly from-the mines.- The outlet from this hopper '1 is controlled by a suitable valve 2 whereby the crushed ore is delivered at suitable intervals and in definite quantities to a furnace 3 which performs the function of pre-heati'ng the ore-and bringing it to a temperature approximating a'red heatbefore'it' is passed through a reducing step. It will of course be understood that the pre-heating chamber 3 may be .either'of a stationary or rotary type and is provided with suitable burners for igniting the gas and a. sufficient quantity of air is supplied thereto from an apparatus to be presently described. This pre-heating step is quite an important one since it rendersthe ore porous and amenable to the action of the hydrocarbon gases durmg the reducmg ste and lnthe case of ores contalning oxids 0 iron,

porosity is most essential. The pre-heated' ore is delivered to a reducing furnace-'6 through a valve 4, while a second valve 5 controls the flow of'gas from thefreducing furnace 6 to the pre-heating furnace and enables the gas to be" used under pressure.

Within this reducing furnace 6 the ore is The ore after its deoxidation in the reducing furnace 6, is delivered through control.

valve 7 to a conveyer 8, incased in a water jacket 9, whereby the temperature is lowered and prevents reoxidation.

The conveyer is preferably of the screw type and operated through the medium of a shaft carrying a pulley 10, driven by any desired type of motor. Located adjacent the outlet of the conveyerare a number of rollers "11 suitably mounted and positionedin the path of the ore as it descends in its discharge fromthe conveyer mechanism. These rollers are ofcourse driven in any well known manner and operate to crush the deoxidized the-ore passes through the rollers 11 it falls in close proximity to a magnetic separator ore to a degree of fineness which is best s uit ed. for the extraction .of the particles of native metal from. the silicious material to which they adhere in the treated ore. As.

12 which operates to pull the iron particles to one side and separate them from the other material,-the bin 13 serving to receive the extracted iron while the dross falls di; rectly into a (bin 14. The bin 13 now contains all of the valuable material which is next dry screened and the flake or flattened particles of material are separated and melt.-

ioc

ed.. The residual portion from the dry' screening which consists of dust and parts ofjthe metal, is combined with a suitable I material such as coke,coal, peat, or other substance into a 'briquet. These briquets must necessarily be of great purity since they arecomposedmainly of metal and metallic oxids and are readily melted in 'a cupola furnace into very pure metal.

designates a retort heated by any suitable means in which a hydro-carbon gas is generated and passes through the valve116 .and byithe conduit 17 to the reducing fur nace 6' whereby the oxids are reduced to a metallic state. i

' lddes'ignates a fan driven in any well knownmanner and blowing a1r from a conduit-19 to the pre-heater 3 from which it is I discharged to anexhaust ofa conduit 21.

Itwill be apparent that this auxiliary air supply is necessary in order to combine with the-gas delivered from the reducing'furnace (i top'roduce aninflammable mixture.

-Inthe modification of Fig. 2, an: apparatus is shown-embodying my process which is especially adapted for use where fine ores,

as sands, which have been-eroded, crushedand concentrated by nature and more particularly that type of ore known as --iron sandsare to be treated. In this form the reducing furnace 7 should-,be mounted in any'suitable manner for rotation in order that the sand may be prevented from packing, in whichcondition it is not amenable to the gas treatment. It has been found in practice that in a stationary reducing furnace through which sand ore is passed great difliculty is experienced by the sand becoming packed and thereby thegreater part of the ore does not come in contact- 'With the hydro-carbon gas and consequently its reduntion is, imperfectly carried out. In order, therefore, to convey the iron sand reducing furnace 7 a rotatable pre-heating furnace 5 is provided which automatically delivers the ore into a chamber 6" from which it passes to the revolving reducing furnace 7 8 designates a hopper delivering the ore to a'conveyer cylinder 9 in which a con- 'veyer similar to that .of Fig. 1 is operated by water cooling cylinder l0 surrounds the. w same as-described for the previous figure means of a shaft carrying pulley 11? and a outlet of the conveyer are suitablyposit-ioned to receive the Adjacent the rollers 12 ore" and crush it to a suitable degree of fine-- 'ness to be operated upon by a magnetic separator 13*, which serves to deliver'the'extractd metal to-the bin 14* while the other material descends into a. bin 15". v

18 designates a retortin which the gas isgenerated in a manner similar to that.

before described, the gas being delivered by meansof a conduit 16* to the hopper 8 and ,y to the rotary essary to ing ore to the.

ent preferred by me,

controlled in its valve 17".

1 9 designates a fan blower supplying air pro-heating chamber through the conduit 20*, the same exhausting through the pipe 31 and the conduit'22". It will be understood that no air must be allowed to enter the chambers 6", 7", 8", as no combus tion should takeplace until the gashas left these chambers and passed to the pre-heating chamber 5*. Provision is of course necprevent danger from explosion and pilot burners are suitably positioned to light passage by means of the the gases at the proper points;

'There are of course many methods and ways of effecting the results that I obtain and my process may with some ores be successfully operated without the use of'a cooldevice. It will be noted that as the metallic particles,

oxid's and dross leave the rollers that they are in a state ready for separation,-

which usually takes place in some type of concentrator aswhere iron ores are under treatment, magnetic separation may be successfully operated while other metals, such as copper, silver or the like, dry concentration1 operating with a suction draft may be use Particular attention -is directed to the novel method of combining the metallic particles into briquets ready'for melting. Any' stood that the various instrumentalities of 'which my invention consists can be variresidual carbon, remainously arranged andorganized andtha-t my invention is not limited to the precise arrangement and organization-of-these instrumentalitles as herein shown and described.

It will now'be apparent that I have devised a novel and useful construction which embodies the features of advantage enumerated as desirable in the statement of the invention and the above description and while I have in described the preferred embodiment thereof which has been found in practice to'give satisfactory and reliable results, it is to'be understood that the same .is susceptible of modification in various particulars "without departing from thcspirit or scope of the inthe present instance shown and vention or sacrificing any of its advantages.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is 1. The method of treating ore which consists of heating said ore by gas under combustion, passing through the heated ore a current of hydrogenous gas and discharging the ore into a water jacketed cooling device to prevent immediate reoxidation and crushing the cooled material to a suitable fineness.

2. The method of treating ore which 'consists of preheating a quantity of ore, passing a volume of air through said ore during the preheating, delivering the ore to a reducing furnace, and subjecting it to a current of hydrogenous gas and subjecting the reduced ore to a cooling action to prevent reoxidation.

3. The method of treating ore which consists of preheating a quantity of ore, passing a volume of air through said ore during the preheating, delivering the ore to a reducing furnace, and subjecting it to a current of hydrogenous gas and subjecting the reduced ore to a cooling action to prevent reoxidation and separatingthe metallic parts from the dross and oxids.

GEORGE FREDERICK, KENDALL.

Witnesses: E. HAYWARD FAIRBANKS, C. D. MCVAY. 

